Pneumatic treating recovery head for dehydrated ore



May 1942- A. K. ANDREWS 2,281,816

' PNEUMATIC TREATING RECOVERY HEAD FOR DEHYDRATED ORE Filed Jan. 21, 1959 ZSheets-Sheet 1 1 n I l as 23 I9 V I0 O 14 f l I l I8 v '5 I5 k 5 I(5- l7 1 2/ I 25 3 25 l o I 29 i 29 26 E 0 I r I U :Thgl q o INVENTOR I Alb t/T.Andrews rrw] z 32 BY er ATTOl i g y 5, 1942- A. K. ANDREWS 2,281,816

PNEUMATIC TREATING RECOVERY HEAD FOR DEI-IYD RATED ORE Filed Jan. 21, T 1939 2 Sheets-Sheet 2 I INVENTOR 2 3| 32 Albert K. Andrews :IFiy. 12' I ATTORN/ Patented May 5, 1942 1 PNEUMATIC TREATIN FOR DEHYD G RECOVERY HEAD RATED ORE Albert K. Andrews, Vancouver, Wash. Application January 21, 1939, Serial No. 252,143

9 Claims.

My invention relates to precious metal recovery device in which the precious metal concentrate is practically ready for reduction to bullion.

The primary purpose of my present invention is for the recovery of the precious metal concentrate from desert placer.

A further object of my invention is to provide a relatively simply constructed device, one that is amenable to expansion to give the same flexibility, one that is adapted for the treating of a large tonnage of material, and one that is susceptible of practically continuous operation Without the incident shut-downs that are many times encountered in placer mining operations.

Another object of my invention is to provide a device for treating of desert placer wherein water is not necessary in the carrying out of the mining operations.

A still further object of my invention is to so construct the device as a unit to permit its frequent change of location with a minimum of effort due to i s inherent construction and its light weight construction. The invention is comprised primarily of a bin that will be common to a number of treating heads in which the mass of material may be deposited by any suitable lifting means, as through the use of a conveyer, or through the use of a bucket-hoist operated by a chain or by any other suitable means. A plurality of hoppers are spaced along the under side of the bin to permit a discharge of material from the base of the hopper through a common communicating pipe to a treating head disposed below each of the discharge hoppers with each of the pipes conducting the material from the hopper having a flow controlled regulator'to thereby predetermine the amount of material thatwill flow from the hopper to each of the treating heads.

In the operation of my device it is necessary to supply air under controlled pressure, velocity, and volume in order that the mass of the material to be treated may be held substantially in air suspension in its approach to the treating head to thereby permit a deposit only of the materials of high specific gravity upon the head. This requires the making of the head of a suitable material to permit the air in volume and velocity to flow therethrough and yet suiiiciently dense to hold thereupon that material gravity that are not carried away through the action of the air flowing therethrough.

I have found satisfactory results may be obtained where the head is made up of a plurality of concentric sets of spaced rings that are ershown removed from ranged in stepped formation with a wool felt being secured to the respective rings to thereby make concentric rifiles of the felted sheet that forms a collector for the metals of high specific gravity. The small particles of material of low specific gravity being treated are carried away from the case in which the treating head is disposed in suspension as dust particles, the larger particles of low specific gravity flow over the sides of the treating head and into the base of the case where the same may be removed by any suitable off-bearing conveyer. It may be found in many cases desirable to supply relatively dust free air to the base of the treating head to prevent the filling of the pores of the felt with dust to thereby prevent the free-fiowing of the air therethrough. In order to make the air normally free of dust at the intake of the blowing fans or pumps, I provide a dust eliminating, dust cleaning head.

With these and incidental objects in View, the invention consists in certain novel features of construction and combination of parts,the essential elements of which are'set forth in the appended claims, and a preferred form of embodiment of which is hereinafter shown with reference to the drawings which accompany and form a part of this specification.

In the drawings:

Fig. 1 is a fragmentary side view of a pair of treating heads shown in relative position to each other.

Fig, 2 is a plan View of one of the treating heads shown as removed from the support and the casing in which the same works.

Fig. 3 is a section trated in Fig. 2.

Fig. 4 is a schematic sectional View of the cover for the headsuch as wool felt.

' Fig. 5 is a side view of a battery of treating heads shown in position and placement for being fed and supplied'material from a common overhead track.

Like reference characters refer throughout the several views.

I provide a suitable frame I along the top of to like parts bottom of the bin and down spouts 4 communicate the hopper with the treating head that is disposed immediately therebelow. A material flow control and cutofl 5 is disposed Within each side View of the device illusof the tubes 4 and the same is mounted upon a shaft 6 that runs through the wall of the tube 4 to facilitate the same being manipulated by any suitable outside control mechanism that may be manipulated by the operator of the device. A

chest I is superposed the respective treating chambers and suction is created within the chests by any suitable control mechanism such as a suction fan not here shown. The respective casings of parallel devices are connected by a pipe 8 that communicates the respective chests together so that but a single suction creating instrumentality will be required even though a battery of devices are secured together in a common undertaking. The suction would be connected to the end of the discharged chest as illustrated at 9. The treating is carried on within a casing Hi and in order that a proper inspection may be made of the operations going on within each of the casings, I provide suitable window frames l 2 having transparent windows H. The Windows are removable from the casings in order to facilitate the removal of the treating heads therethrough. This may be accomplished by having lugs l3 and I4 disposed at each end of the window and having pins placeable therein so that the removal of the window assembly may be accomplished by raising the window sufficiently to remove the pins from the lugs. It will be noted that the chest I and the'pipe 8 may be made as a unit, that the central portion of the case may be made as illustrated at ID, that the window is associated therewith and that the skirt I5 of the case has a tapering bottom at one side and a verical bottom at the other side in order that the treating head maybe spaced central thereof. Suitable flanges are disposed upon each of the members to facilitate the attachment and the securing of the same together. A supporting tube It is provided. The

tube 16 passes through the flared portion of the bottom of @he lower member that comprises the case and the tube It is coaxial with the pipe 4. The tube i6 is supported by a valve H and a frustoconical hood I8 is provided. The hood l3 and the tube IB have flanged abutting ends to facilitate the attachment of one to the other. A treating head is removably disposed upon the frustoconical member I8, the treating head is comprised of a band 59. The band I!) has a ledge on its inner surface and the ledge rests upon the top of the member IS. A spider frame is superposed the head, the same is made up of cross bars with the outer end of each of the cross bars resting upon the top of the ban-d [9. A plurality of pairs of concentric rings 2! are suspended from the bars 2!) that form the spider and collecting and recovering felt, preferably made of wool, is secured to the respective pairs of concentric rings and the walls of the felt form riiiies 23 that collect the precious metals to be recovered. The apex of the head is illustrated at 24.

When sufficient concentrate has collected within the head the same is removed through the window l2 and a second head is placed in its place. A pipe 25 communicates the valve H with the blower 25 in order that air in sufficient volume and pressure may-be supplied to the frustroconical member 18 and force the air through the head superposed thereabove. The material flowing through the pipe I is deposited above the head. The particles of the mass being deposited above the head that is sufficiently light either is blown from the case In in the form of particles held in suspension within the air stream or the same gravitates and flows over the treating head and flows into the base of the case l5 and outwardly through a discharging pipe which is the dross material which may flow to any suitable off bearing conveyor not here shown. A prime mover 28 is positioned at a suitable location and the same is directly connected to the drive shaft 2'! that is common to each of the blowers 26. A dust collector 29 may be placed at the inlet end of the blower 26 in order that dust free air or at least relatively normal air may be forced into each of the treating heads. It will be noted that the discharge end 3| of each of the pipes 30 through which the dross material flows, terminates at a common level in order that an offbearing conveyor may collect the material and remove the same from beneath the floor 32 or from beneath the housing frame in which the treating heads are placed. This provides a flexible construction that may be made up of a rela tively large number of units all or any one of which may be operated as desired.

Where the volume and velocity of the air is closely controlled and a uniform flow of material is supplied into the head, a large tonnage of desert material may be treated without the wearing of the felts unduly. A device of this kind is adapted for recovering a wide variety of precious metal materials from the microscopic particles to the larger pieces that will be recovered. The recovery is complete, and but little refining is required to reduce the same to bullion.

While the form of mechanism herein shown and described is admirably adapted to fulfill the objects primarily stated it is to be understood that it is not intended to confine the invention to the embodiment herein shown and described, as it is susceptible of embodiment in various form, all coming within the scope of the claims which follow.

What I claim is:

1. In a device of the class described, the combination of a fabricated case, a chest superposed the case, a bin superposed the chest, the hoppers being disposed between the chest and the bin, a tube communicating the interior of the hopper with the interior of the case, a flow control disposed within the tube to predeterinine the volume of the material that is to flow through the tube, a treating head disposed within the case and in spaced relation with the discharge end of the tube and in axial alignment therewith, said treating head being comprised of a band for supporting the head assembly, a plurality of pairs of concentric rings, with the rings of each pair being spaced apart vertically, a felt fabric disposed about the respective pairs of concentric rings, with the fabric passing over the upper ring and under the lower ring of each pair, cross bars disposed above the pairs of concentric rings and resting upon their outer ends upon the top of the band, said cross bars extending radially from the center of the treating head to the rim of the head, a frusto-conical hood for supporting the treating head, with the head being freely removable from the hood through the side wall of the case, means for supplying the air in controlled pressure, volume, and velocity to the base end of the frustoconical hood, and means for disposing dross material through the base of the case and for off-bearing the same.

2. In a device of the class described in combination, a treating head; said treating head being made of a frusto-conical hood, a band disposed upon a removably secured to the top end of the frusto-contical hood, a spider-like frame made up of bars, the outward end of which rests upon the top of the band, a plurality of sets of upper and lower concentric rings suspended from the bars of the spider, a wool fabric sheet supported by the concentric rings with the top and bottom concentric rings being arranged in stepped formation and the fabric sheet passing over the top and under the bottom of each of the pairs of concentric rings to form treating riflies on the top surface of the treating head, and means for supplying clarified air in controlled velocity and volume into base end of the treating head and for forcing the air upward through the treating head.

3. A treating head of the class described comprised of a frusto-conical supporting base for the head, means for supplying clarified air under pressure through the frusto-conical member, a head for the frusto-conical base support, said base member resting upon and being removably secured to the frusto-conical head, the treating surface of said head being comprised of a spider and sets of concentric rings arranged in stepped formation below the spider, and a wool felt sheet arranged in riffle formation and supported by the concentric rings, and means for releasing a controlled volume of material above and in spaced relation with the top of the treating head.

4. In a device of the class described, in combination, a treating head made up of a band, a spider superposed the band and being supported thereby, a plurality of pairs of concentric rings arranged in stepped formation, suspended from the bars comprising the ported by the concentric rings, with said fabric passing over the top and under the bottom of each pair of concentric rings.

5. A device for recovering precious metal from dried concentrate composed of an open ended treating head, a plurality of concentric rings having a porous covering forming a riflled porous diaphragm disposed within the treating head, means for admitting a controlled amount of air below the diaphragm, means for a continuous disposal of all ore and dust with specific gravity lighter than that of the precious metal from the treating area and means for removing the treating head through the side of the clevice.

6. In a device of the class described the combination of a bin, means for supplying material to be treated to the bin, a plurality of hoppers suspended from the bin and each communicating with the bin, a plurality of cases disposed below the hopper, a treating head disposed within each of the cases, the top of the treating head being made of a wool fabric and passing over and under a series of sets of rings with the rings of each set having a different diameter, and the top ring of each set being at a different spider and a fabric supelevation than the top rings of adjacent sets of rings, and the fabric passing over the top ring and under the bottom ring of each set, said treating heads being removable through the side Wall of the case, means for flowing controlled quantities of material from the hopper to the treating head, means for supplying air in controlled pressure, velocity, and volume vertically through the treating head, means for clarifying the air to be supplied in advance of its passing through the treating head and means for offbearing dross material flowing from the base end of the case.

7. In a device of the class described the combination of a treating head, a case surrounding the treating head with the walls of the case being in spaced relation with the rim of the treating head, means for delivering a controlled amount of material to be treated into the case and for depositing the same upon the top of the treating head, said top of the treating head being fashioned of a wool fabric sheet formed into a series of concentric riffies, with the concentric rifiles being arranged in stepped formation and with the center rifile being of greater height and with the riflles uniformly decreasing in height, means for exhausting treating air from the case, means for flowing a controlled volume of air upward through the treating head, means for clarifying the air before its entry into the treating head and means for off-bearing the dross material from the base end of the case.

8. In a device of the class described, comprising in combination a head that is circular in plan, and having a fabric felt top, with the felt being removable from the head and the felt disposed in concentric rings that are arranged in stepped formation to form riflies of the felt top, a feed pipe disposed above the head and arranged to feed material to be treated upon the felt top, with the head being superposed an air pipe and means for delivering air in controlled amount and under pressure into the air pipe, so as to flow the air through the riiiied felt.

9. A treating head for desert placer mining which is comprised of an annular band, pairs of concentric top and bottom rings arranged in stepped formation disposed within the band, and supported by the band, and a fabric covering disposed within the head and supported under tension by the concentric rings, with the fabric passing over and under the respective pairs of concentric rings, with the top rings being arranged in stepped formation, said treating head being disposed within a casing, and means for supplying clarified air under pressure and volume and for forcing the same upward through the head and through the fabric sheet.

ALBERT K. ANDREWS. 

